GMC sierra 2002 5.3L 1500

[Dcas3443]

I recently removed a spark plug from my sierra to identify what was in the truck part # 41-974 . I have scoured all sites to find spark plugs that I can use on my truck that are iridium I keep having 41-110 show up however they say it is not compatible with my vehicle. Does anyone know which plugs I can use for my vehicle .

 

[Miami-Dade]

@Dcas3443 Moved you here from Site News.
Welcome from Miami Beach!

 

[Fless]

Welcome to TYF.

A while back I messaged with GM about the plugs for my '04, and they said they no longer recommend the iridium plugs. They recommend 41-962 double platinum.

Other members here will have plug recommendations for you.

 

[SilverSport]

I also noted some time ago that the "OEM" spark plug replacements are the double platinum 41-962 AC Delco

Bill

 

[afpj]

I also read that GM changed their recommendations for the GMT800 regarding spark plugs, and also a change in gap size from the original label. Do the 41-962s have to be regapped? I can't remember that part.

 

[SilverSport]

RockAuto.com shows the AC Delco 41-962 come pre gapped at .040 and the recommended gap should be .040

Bill

 

[rockola1971]

You never install a "pre gapped" spark plug. Always check them to make sure the proper gap is made. Workers and machines make mistakes, shipping is seldomly problem free and god only knows who has had those spark plugs in their hands before you (Returns).

 

[PPV_2018]

You never install a "pre gapped" spark plug. Always check them to make sure the proper gap is made. Workers and machines make mistakes, shipping is seldomly problem free and god only knows who has had those spark plugs in their hands before you (Returns).

THIS^^^^^. Always gap your plugs or at least verify they are the correct gap if they are “pre-gapped”.

Also, don’t bother with the iridium. As others have said, Double Plats would be a good replacement for OEM. AC/Delco is GM brand. Rockauto says copper plug for GM original equipment .. But I doubt that’s correct. Hard for me to believe they were running copper from the factory since before the Millenium.

 

[Fless]

Verify the gaps, but be careful when checking them so you don't damage the electrodes.

See NGK's recommendations:

Do I need to set the "gap" when installing a new set of plugs? - NGK Spark Plugs

DIY Tip: An incorrect plug gap can contribute to a high rate of misfires, so it’s important for you to know the right gap for your engine.

ngksparkplugs.com